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Whipping Knot
A whipping knot or whipping is a binding of twine or whipcord around the end of a rope to prevent its natural tendency to fray. Some whippings are finished cleanly, as by drawing the bitter end of the cordage beneath the whipping itself. Others are tied off or have the end(s) of the twine sewn through the rope. According to ''The Ashley Book of Knots'', "The purpose of a ''whipping'' is to prevent the end of a rope from fraying ... A whipping should be, in width, about equal to the diameter of the rope on which it is put ... wo sailmaker's whippings a short distance apart, are put in the ends of every reef point, where the constant 'whipping' against the sail makes the wear excessive; this is said to be the source of the name ''whipping''."Ashley, Clifford W. (1944). ''The Ashley Book of Knots'', p.547. Doubleday. . The other type of stopping knot is a seizing knot. Whipping is suitable for synthetic and natural stranded and braided lines, including 3-strand rope, 4-strand ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portuguese Whipping
A whipping knot or whipping is a binding of twine or whipcord around the end of a rope to prevent its natural tendency to fray. Some whippings are finished cleanly, as by drawing the bitter end of the cordage beneath the whipping itself. Others are tied off or have the end(s) of the twine sewn through the rope. According to ''The Ashley Book of Knots'', "The purpose of a ''whipping'' is to prevent the end of a rope from fraying ... A whipping should be, in width, about equal to the diameter of the rope on which it is put ... wo sailmaker's whippings a short distance apart, are put in the ends of every reef point, where the constant 'whipping' against the sail makes the wear excessive; this is said to be the source of the name ''whipping''."Ashley, Clifford W. (1944). ''The Ashley Book of Knots'', p.547. Doubleday. . The other type of stopping knot is a seizing knot. Whipping is suitable for synthetic and natural stranded and braided lines, including 3-strand rope, 4-strand c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aglet
An aglet ( ) or aiglet is a small sheath, often made of plastic or metal, attached at each end of a shoelace, a cord, or a drawstring. An aglet keeps the fibers of the lace or cord from unraveling; its firmness and narrow profile make it easier to hold and easier to feed through eyelets, lugs, or other lacing guides. Etymology The word ''aglet'' and its variant ''aiglet'' come from the Middle French and Old French word ', the diminutive of ', meaning "needle, pin", which in turn comes from the Late Latin ' ("ornamental pin, pine needle"), diminutive of ''acus'', the Latin word for a needle or pin.Picken, Mary Brooks: ''The Fashion Dictionary'', Funk and Wagnalls, 1957. (1973 edition ) History Aglets were originally made of metal, glass, or stone, and many were very ornamental. Wealthy people in the Roman era would have their aglets made out of precious metals such as brass or silver. Before the invention of buttons, they were used on the ends of the ribbons used to fast ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Block (sailing)
In sailing, a block is a single or multiple pulley. One or a number of '' sheaves'' are enclosed in an assembly between ''cheeks'' or ''chocks''. In use, a block is fixed to the end of a line, to a spar, or to a surface. A line (rope) is ''reeved'' through the sheaves, and maybe through one or more matching blocks at some far end, to make up a tackle. The ''purchase'' of a tackle refers to its mechanical advantage. In general the more sheaves in the blocks that make up a tackle, the higher its mechanical advantage. The matter is slightly complicated by the fact that every tackle has a ''working end'' where the final run of rope leaves the last sheave. More mechanical advantage can be obtained if this end is attached to the moving load rather than the fixed end of the tackle. There are various types of blocks that are used in sailing. Some blocks are used to increase mechanical advantage and others are used simply to change the direction of a line. A ''ratchet block'' turn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Back Splice
The human back, also called the dorsum (: dorsa), is the large posterior area of the human body, rising from the top of the buttocks to the back of the neck. It is the surface of the body opposite from the chest and the abdomen. The vertebral column runs the length of the back and creates a central area of recession. The breadth of the back is created by the shoulders at the top and the pelvis at the bottom. Back pain is a common medical condition, generally benign in origin. Structure The central feature of the human back is the vertebral column, specifically the length from the top of the thoracic vertebrae to the bottom of the lumbar vertebrae, which houses the spinal cord in its spinal canal, and which generally has some curvature that gives shape to the back. The ribcage extends from the spine at the top of the back (with the top of the ribcage corresponding to the T1 vertebra), more than halfway down the length of the back, leaving an area with less protection between the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aramid
Aramid fibers, short for aromatic polyamide, are a class of heat-resistant and strong synthetic fibers. They are used in aerospace and military applications, for ballistic-rated bulletproof vest, body armor cloth, fabric and ballistic composites, in marine cordage, marine hull reinforcement, as an asbestos substitute, and in various lightweight consumer items ranging from phone cases to tennis rackets. The chain molecules in the fibers are highly oriented along the fiber axis. As a result, a higher proportion of the chemical bond contributes more to fiber strength than in many other synthetic fibres in the world. Aramids have a very high melting point (>). Common aramid brand names include Kevlar, Nomex, and Twaron. Terminology and chemical structure The term ''aramid'' is shortened from ''aromatic polyamide''. It was introduced in 1972, accepted in 1974 by the Federal Trade Commission of the USA as the name of a generic category of fiber distinct from nylon, and adopted by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polypropylene
Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer Propene, propylene. Polypropylene belongs to the group of polyolefins and is Crystallization of polymers#Degree of crystallinity, partially crystalline and Chemical polarity#Nonpolar molecules, non-polar. Its properties are similar to polyethylene, but it is slightly harder and more heat-resistant. It is a white, mechanically rugged material and has a high chemical resistance. Polypropylene is the second-most widely produced Commodity plastics, commodity plastic (after polyethylene). History Phillips Petroleum chemists J. Paul Hogan and Robert Banks (chemist), Robert Banks first demonstrated the polymerization of propylene in 1951. The stereoselective polymerization to the isotactic was discovered by Giulio Natta and Karl Rehn in March 1954. This pioneering discovery led to large-scale commercial producti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyester
Polyester is a category of polymers that contain one or two ester linkages in every repeat unit of their main chain. As a specific material, it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include some naturally occurring chemicals, such as those found in plants and insects. Natural polyesters and a few synthetic ones are biodegradable, but most synthetic polyesters are not. Synthetic polyesters are used extensively in clothing. Polyester fibers are sometimes spun together with natural fibers to produce a cloth with blended properties. Cotton-polyester blends can be strong, wrinkle- and tear-resistant, and reduce shrinking. Synthetic fibers using polyester have high water, wind, and environmental resistance compared to plant-derived fibers. They are less Fireproofing, fire-resistant and can melt when ignited. Liquid crystalline polyesters are among the first industrially used liquid crystal polymers. They are used for their mechanical propert ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Polyethylene
Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging (plastic bags, plastic films, geomembranes and containers including bottles, cups, jars, etc.). , over 100 million tonnes of polyethylene resins are being produced annually, accounting for 34% of the total plastics market. Many kinds of polyethylene are known, with most having the chemical formula (C2H4)''n''. PE is usually a mixture of similar polymers of ethylene, with various values of ''n''. It can be ''low-density'' or ''high-density'' and many variations thereof. Its properties can be modified further by crosslinking or copolymerization. All forms are nontoxic as well as chemically resilient, contributing to polyethylene's popularity as a multi-use plastic. However, polyethylene's chemical resilience also makes it a long-lived and decomposition-resistant pollutant when disposed of improperly. Being a h ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nylon
Nylon is a family of synthetic polymers characterised by amide linkages, typically connecting aliphatic or Polyamide#Classification, semi-aromatic groups. Nylons are generally brownish in color and can possess a soft texture, with some varieties exhibiting a silk-like appearance. As Thermoplastic, thermoplastics, nylons can be melt-processed into fibres, Thin film, films, and diverse shapes. The properties of nylons are often modified by blending with a variety of additives. Numerous types of nylon are available. One family, designated nylon-XY, is derived from diamines and dicarboxylic acids of carbon chain lengths X and Y, respectively. An important example is nylon-6,6 (). Another family, designated nylon-Z, is derived from amino acid, aminocarboxylic acids with carbon chain length Z. An example is nylon-[6]. Nylon polymers have extensive commercial applications, including uses in textiles and fibres (such as apparel, flooring and rubber reinforcement), molded components fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dacron
Polyethylene terephthalate (or poly(ethylene terephthalate), PET, PETE, or the obsolete PETP or PET-P), is the most common thermoplastic polymer resin of the polyester family and is used in fibres for clothing, containers for liquids and foods, and thermoforming for manufacturing, and in combination with glass fibre for engineering resins. In 2016, annual production of PET was 56 million tons. The biggest application is in fibres (in excess of 60%), with bottle production accounting for about 30% of global demand. In the context of textile applications, PET is referred to by its common name, polyester, whereas the acronym ''PET'' is generally used in relation to packaging. PET used in non-fiber applications (i.e. for packaging) makes up about 6% of world polymer production by mass. Accounting for the >60% fraction of polyethylene terephthalate produced for use as polyester fibers, PET is the fourth-most-produced polymer after polyethylene (PE), polypropylene (PP) and polyvinyl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
